共查询到19条相似文献,搜索用时 156 毫秒
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文章选取具有非线性光学活性的偶氮化合物作为研究对象,合成了一组含不同取代基和不同推-拉电子结构的偶氮化合物,并通过红外光谱、紫外-可见吸收光谱、元素分析、核磁共振氢谱等方法对所合成的偶氮化合物结构进行了表征;用单光束Z-扫描的方法对所合成的偶氮化合物的三阶非线性光学性能进行了测试,并结合理论计算分析研究了分子结构对偶氮化合物三阶非线性光学性能的影响。 相似文献
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合成和研究了两种新型的过渡金属偶氮化合物,利用红外光谱和紫外光谱对它们进行了初步的结构表征,结果表明金属离子已成功地连接在偶氮分子上。 相似文献
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以对氨基苯磺酸和苯胺为底物 ,合成了偶氮苯 - 4-磺酸钠。用UV/Vis光谱、FT -IR光谱对合成产物进行了鉴定 ,表明产物结构正确。为合成类似结构的偶氮染料提供了实验依据 相似文献
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苯并三唑类紫外线吸收剂的现状及发展趋势 总被引:8,自引:1,他引:7
综述了不同种类的紫外线吸收剂,着重介绍了苯并三唑类紫外线吸收剂。苯并三唑类紫外线吸收剂由于性能优异而广泛应用于各种高分子合成材料和制品中。但由于其相对分子质量较小,在高分子材料加工过程中,容易通过向表面迁移、表面挥发而引起损失,所以其耐光性比较差。在苯并三唑类紫外线吸收剂分子中引入可聚合的基团使它可以和不同的单体聚合成高分子化合物。从共价键到聚合物链的转变使其在介质中更稳定,更不易迁移和挥发。含有可聚合基团的紫外线吸收剂相比普通的紫外线吸收剂显示出了相当优良的耐光稳定性。 相似文献
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合成了8个具有不同结构的羟基苯基苯并咪唑类荧光化合物,通过1 H NMR,IR对其进行了结构表征,并研究了它们在甲醇溶液中的光谱性质及取代基对光谱性质的影响。该类化合物的荧光量子产率在0.006~0.75之间,Stokes位移大(>117nm)。实验结果表明,化合物上所连取代基的性质对其光谱有显著影响,具有推电子基团的羟基苯基苯并咪唑类化合物在光激发下出现荧光双发射峰,而具有吸电子基团的化合物在光激发下仅出现激发态质子转移荧光发射峰,表现出Stokes位移大和荧光量子产率高的优点。 相似文献
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介绍了烷氧基化产品的生产工艺、催化剂及应用。应用方面主要介绍了烷氧基化产品接人特殊基团后的改性应用,即各种封端聚醚的特殊用途。 相似文献
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Dr. Annika Gross Daniel Habig Prof. Dr. Nils Metzler‐Nolte 《Chembiochem : a European journal of chemical biology》2013,14(18):2472-2479
The chemically stabilized somatostatin‐derived cyclic octapeptide octreotate has a number of interesting applications in medicinal chemistry. Here, a number of different organometallic derivatives of octreotate were prepared, and their properties were investigated. Specifically, we report the synthesis and characterization of ruthenocene, ferrocene, and cobaltocenium octreotate derivatives and their fluorophore‐labeled conjugates as well as a dicobalt hexacarbonyl alkyne functionalized octreotate. To provide further insights into their characteristics, the log P values and electrochemical properties of the novel metal conjugates were compared. For biological activity, we determined their toxicity in three different cell lines. Cellular uptake and colocalization of selected compounds were studied by fluorescence microscopy with particular focus on efficiency and specificity of their uptake through the somatostatin receptor SSTR to elucidate the value of the metallocene head group for its potential use as a nontoxic and universal peptide label. 相似文献
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Modified polyacrylamide hydrogels and their application in removal of heavy metal ions 总被引:3,自引:0,他引:3
Modified crosslinked polyacrylamides having different functional groups were prepared by Mannich reaction using different amine compounds such as ethylenediamine (EDA), diethylenetriamine (DETA) and triethylenetetramine (TETA) and sulfomethylation reaction. Products were characterized by determination of their basic group content (BGC), hydroxymethyl group content (HMG), equilibrium degree of swelling (EDS) and FT-IR spectra. For Mannich reactions, BGC and EDS changed with amount of employed amine compounds, reaction time and temperature. Sulfomethylation reactions gave products with high BGC and very high EDS. FT-IR spectroscopic analysis confirmed that a parallel hydrolysis reaction occurred along with the expected modification reactions. The products were used for removal of Cu(II), Cd(II) and Pb(II) ion under competitive and non-competitive conditions at different pH. The metal ion removal capacities changed depending their BGC and EDS. While the Mannich products were selective towards Cu(II) ion, the sulfomethylation products were highly selective to Pb(II) ions. The polymers were used several times by regeneration without loss of adsorption capacity and changing of selectivity properties. 相似文献
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为探究不同酯类单体对缓释型聚羧酸减水剂分散性能及分散保持性能的影响规律和作用机理,采用不同分子结构酯类单体作为改性原料制备不同缓释型聚羧酸减水剂,并通过水泥浆体经时流动度、Zeta电位、总有机碳、电导率、傅里叶红外光谱、核磁共振氢谱等测试分析其宏观分散性能及分散保持性能与微观结构的变化规律及作用机理。结果表明:采用单酯类单体(丙烯酸羟乙酯、丙烯酸羟丙酯、丙烯酸甲酯)和双酯类单体(马来酸二甲酯)作为功能单体改性的缓释型聚羧酸减水剂分散保持性能较为优异,4 h时流动度相比初始流动度仍有所提升,同时相比未改性空白组,4 h 时流动度显著提升,后期分散性能更为优异。主要机理为:碱性环境下酯基在水泥浆体中缓慢水解出锚固基团羧基阴离子,发挥分散作用;不同分子结构的酯类单体位阻效应和基团电负性存在差异,导致水解速率和水解程度不同,从而使各种缓释型聚羧酸减水剂分散性能及分散保持性能存在差异。 相似文献